Abstract: The output voltage of a Wheatstone bridge type electrical circuit compris four main resistances (J.sub.1 to J.sub.4) having substantially the same ohmic value, R, and substantially the same temperature coefficient of resistance, .alpha., is made independent of temperature differences existing between the branches of the bridge by addition, in each of the branches, of a compensation element (r.sub.1 to r.sub.4) in series with the main resistance, each compensation element being physically located very close to a main resistance situated in one of the adjacent branches of the bridge so as to have the same temperature as that main resistance. The compensation elements have the same ohmic value r and the same temperature coefficient of resistance .beta., with R.alpha.=r.beta., r being less than R and, preferably, r/R.ltoreq.1/2, so as to limit the loss of sensitivity of the Wheatstone bridge to variations in the resistances of the bridge.

Abstract: A pressure sensor includes a body, a pressure inlet tube housed in the body and having a pressure inlet opening defined therein for introducing oil pressure, and a pressure sensor unit affixed to a proximal end surface of the pressure inlet tube covering the pressure inlet opening to convert the oil pressure to an electrical signal. An oil flow decelerating structure is disposed to a distal end side of the pressure inlet tube for reducing the flow rate of oil.

Abstract: The apparatus of the invention includes a sensor header and a sensor cover which are coupled to a prior art diaphragm assembly. The sensor header is provided with two piezoresistive silicon membrane strain gauges. One side of both strain gauges is exposed to fluid at upstream high pressure. The other side of the first strain gauge is exposed to fluid at downstream low pressure and the other side of the second strain gauge is exposed to the atmosphere. The sensor header is provided with a first port which is fluidly coupled to the first membrane strain gauge and extends to the surface of the header at a first location. The sensor header is provided with a second port which is fluidly coupled to the second membrane strain gauge and extends to the surface of the header at a second location. The sensor cover defines two isolated annular spaces around the sensor header, a first annular space around the first location and a second annular space around the second location.

Abstract: A pressure transducer that includes at least two sensors having substantially similar or substantially identical error characteristics, wherein each sensor is arranged to be subjected to an applied pressure and the outputs of the sensors are electrically coupled so that errors associated with one sensor are compensated by errors associated with the other sensor. The sensors may be substantially identical silicon sensors formed in close proximity on the same wafer.

Abstract: A thin, flexible foil acts as the membrane of the transducer. It is circumferentially connected to a rigid support structure which connects the foil mechanically with the transducer's driving coil. The foil is equipped with strain sensors which indicate the pressure upon the foil.

Abstract: A pressure sensor prevents the occurrence of a large deformation or breakage of the diaphragm in a strain gage-type pressure sensor utilizing a thin plate-shaped insulating body as the diaphragm. The pressure sensor comprises an insulating diaphragm having a strain gage on its surface and a substrate positioned opposing the surface of the diaphragm on which the strain gage is mounted and kept a predetermined distance away from the surface. The diaphragm can be formed of material such as ceramic of alumina, zirconia or the like, silicon or crystal. The substrate can be formed of either the same material as the diaphragm, or the surface opposing the diaphragm can be formed of an insulator disposed on metal. The diaphragm and the substrate can be affixed using a low-melting glass.

Abstract: A non-zero temperature coefficient of offset (Tco) in a semiconductor device (5) is adjusted by reducing the amount of adhesive material used to secure a first structure to a second structure. An adhesive layer (14) used to secure a sensor die (11) to a constraint die (12) in a pressure sensor application is reduced in thickness and/or formed so that adhesive material does not completely cover the constraint die (12). The Tco is further adjusted by reducing the amount and/or patterning the adhesive layer (18) used to secure the sensor (10) to its package (16).

Abstract: A semiconductor differential pressure measuring device comprising two measurement diaphragms and two detection sensors provided in a semiconductor substrate using micromachining techniques, and a computing circuit which computes the differences between the two sensor outputs, wherein a communicating hole is provided for applying pressure to each diaphragm so that the diaphragms operate in opposite phases by differential pressure, and two detecting sensors are provided on each diaphragm for detecting displacement or strain of each diaphragm caused by the differential pressure applied to the respective diaphragm, whereby detecting the differences in displacement or strain cancels the static pressure error and temperature error so that the invention has excellent temperature and static pressure characteristics, and whereby the computing circuit comprises a bridge using the two detecting sensors, which substantially reduces the cost of the device.

Abstract: A media compatible microsensor structure (11) for sensing an environmental condition in a harsh media includes an inorganic protective film (17) covering portions of the structure that will be exposed to the harsh media. In one embodiment, the microsensor structure (11) includes a microsensor package (12), a microsensor device (16) bonded to the microsensor package (12), a leadframe (13), a connective wire (14) connecting the microsensor device (16) to the leadframe (13), and an inorganic protective film (17) formed on all or portion of the exposed surfaces of the structure.

Abstract: A single, disposable differential transducer having a molded plastic body in which there is a pair of chambers separated by a strain gage electronic chip that flexes in accordance with the difference in the pressures between the two chambers. The plastic housing has inlets to allow communication with the chambers and the overall unit is readily manufactured of inexpensive components that allow disposability of the unit when it has been used on a patient. The pressure transducer chambers are isolated from each other such that differing locations of the patient may be sensed for pressure at the same time without the risk of inadvertant cross-contamination.

Abstract: A micromachined hot-wire anemometer having fast response times and higher sensitivities than conventional hot-wire anemometers is provided by micromachining doped polysilicon wires carried on silicon supports cantilevered from a substrate including one or more insulating layers disposed between said substrate and supports. The micromachined polysilicon hot-wire anemometer is fabricated using surface micromachining techniques.A shear stress sensor is micromachined to define a thin diaphragm over a cavity defined in a substrate underlying the diaphragm. The cavity is evacuated, sealed, and a thermistor disposed over the diaphragm. The thermistor is thus thermally insulated from the substrate and provides a low profile shear stress sensor for measuring flow rates in boundary layers above a flow surface.

Abstract: A combustion pressure sensor suitable for a highly precise combustion control system of an automobile engine and a sensing system using the sensor. The combustion pressure sensor includes a SOI substrate having a three-layered structure of a first silicon plate, a thermal oxide film, and a second silicon plate, wherein a combustion pressure is sensed on the basis of a pressure or a force applied to the first silicon plate.

Abstract: A differential pressure transducer for measuring a pressure differential between a first pressure source and a second pressure source. The differential pressure transducer includes a displacement element and a sensing element coupled to the displacement element. The displacement element moves in a linear direction and deflects the sensing element to provide a signal that is proportional to the movement of the displacement element when the first and second ends are subjected to the pressures at the pressure sources. The differential pressure transducer can also include a force transfer beam that connects the displacement element and the sensing element. The sensing element can include a sensing beam and a strain gauge mounted on the beam to provide an electrical signal proportional to the strain in the beam induced by the deflection of the beam. The force transfer beam and the sensing element can be portions of a unitary member formed as a stamped part.

Abstract: A semiconductor substrate has a surface layer disposed underneath a gate electrode of a field-effect transistor and having a resistance higher than the resistance of an inner layer which is formed in the semiconductor substrate below the surface layer. The surface layer is formed when a donor doped in the surface layer and an acceptor generated based on a compressive stress which is developed in the surface layer when the gate electrode is formed substantially cancel out each other. The field-effect transistor operates alternatively as a junction field-effect transistor when the surface layer is turned into a p-type structure when a compressive stress is generated in the surface layer and a metal semiconductor field-effect transistor when the surface layer is turned into an n-type structure when a tensile stress is generated in the surface layer.

Abstract: A carrier assembly includes a sensor housing having first and second housing portions and a sensor cavity formed therebetween for carrying a sensor. A carrier assembly couples to the sensor and provides electrical connections which extend from the sensor and between the first and second housing. The sensor couples to a fluid and provides a sensor electrical output.

Abstract: A guidewire having pressure sensing capabilities for measuring the pressure of liquid in a vessel comprising a flexible elongate member and having proximal and distal extremities and having an outside diameter of 0.018" or less. The distal extremity of said flexible elongate member is adapted to be disposed in the liquid in said vessel. A housing is carried by the flexible elongate member and has a diameter substantially the same as the diameter of the flexible elongate member. The housing has a space therein with a pressure sensor mounted in the space in the housing. The pressure sensor has a diaphragm that is sensitive to changes of pressure in the liquid in the vessel. The diaphragm is rectangular in shape and is bordered by a rim surrounding the well. A backing plate is formed of an insulating material bonded to the crystal and serves to reinforce the rim of the crystal of semiconductor material.

Abstract: A form pressure sensor diaphragm and method of making that allows for formation of long rectangular plate structures in semiconducting materials, especially silicon. A plurality or multiplicity of sensors may be constructed on a single chip, thus providing for absolute and relative sensing of pressure on a single device.

Abstract: A device and method for remotely zeroing a hydrostatic pressure compensation device are described which permit a fluid transducer, such as is used in conjunction with an intravenous catheter for the measurement of blood pressure, to be zeroed regardless of its elevation. A hydrostatic pressure compensation tube is placed in closed fluid communication with both faces of the transducer so as to provide the same pressure to each side. As an example, the transducer may measure the deflection with a piezoresistive or piezoelectric crystal or may alternatively utilize a semiconductor membrane with implanted resistive elements. The transducer may be coupled or formed integral to a manifold. In such a device, the transducer may be zeroed at any vertical position.

Abstract: A multi-function differential pressure sensor includes a semiconductor chip, a stationary base having a joining portion joined to a thick wall portion of the semiconductor chip, and a housing joined to the stationary base. The semiconductor chip is provided with a differential pressure detection unit, a static pressure detection unit, and a temperature detection unit. The joining portion of the stationary base is not thicker than the semiconductor chip. The stationary base has one or more thin wall portions located, in a plan view, within a circular pressure sensitive diaphragm of the semiconductor chip.

Abstract: A semiconductor chip, which is preferably designed as a pressure sensor, has on its rear side one or more depressions in which the pressure is measured by correspondingly designed diaphragms which are coupled to piezosensitive circuits. The surface of the depressions and, optionally, the rear side of the semiconductor chip are coated with a protective layer which ensures that the semiconductor is protected from aggressive media. The protective layer thereby makes it possible to use the sensor universally in acids, lyes or hot gases.

Abstract: A pressure sensor comprises a diaphragm mounted on a housing and subject to pressure. Stress sensitive resistors are connected to circuit traces on the diaphragm which in turn are wirebonded to a compensation IC. The IC is directly mounted on the diaphragm principally or wholly in an area which is not subject to flexing. A connector has a dome partially covering the diaphragm and holds terminal blades having ends extending away from the diaphragm and opposite ends carrying bond pads located adjacent the diaphragm. An opening in the dome permits wirebonder access to connect bond pads on the traces with terminal bond pads. A cover is installed over the connector and sensor.

Abstract: A pressure difference measurement transducer with an inner housing divided into two parts transversely to its longitudinal axis has a central diaphragm bearing a pressure sensor clamped between the two housing sections. One housing section contains an electric lead-through in a bore, an external extension of which lies in an enlarged part of the bore. To simplify the electric lead-through in the manufacture of such a measurement transducer, the bore is arranged parallel to the longitudinal axis of the measurement transducer. At its end towards the other housing section the bore has an enlarged section and at its end away from the other housing section it becomes an outwardly directed transverse bore.

Abstract: A pressure sensor comprises a pressure-sensitive coupler body 2 having one end provided with a diaphragm 8 and strain gage 9 stacked together, an intermediate body 3 containing a printed board 21 and encircling the strain gate 9, and a signal-detective coupler body 4 opposed to the pressure-sensitive coupler body 2 via the intermediate body 3 to define a closed chamber in the intermediate body 3. The printed board 21 and the strain gage 9 are electrically connected by terminal elements 13 extended from the strain gage 9 into slidable contact with conductive elements 25 attached to an edge of the printed board 21. Vibrations or impulses produced in the diaphragm 8 are therefore absorbed by a relative displacement between the terminal elements 13 and the conductive elements 25 to protect the printed board 21 against such vibrations or impulses.

Abstract: A pressure sensor comprises a substrate and a layer defining together with said substrate a pressure sensor cavity, said layer including a diaphragmlike area which is adapted to be acted upon by an external pressure. A micro-miniaturizable pressure sensor of the above-mentioned type, which is used for differential pressure measurement or for relative pressure measurement, is provided on the basis of the features that said cavity is followed by a channel which extends along the surface of said substrate, said channel comprising a layered structure including also the layer which also defines the diaphragmlike area of the pressure sensor, the ratio of the width of the channel to the thickness of the layered structure above the channel being smaller than the ratio of the smallest extension of the diaphragmlike area in the diaphragm plane to the thickness of the diaphragmlike area.

Abstract: To ensure insensitivity to electromagnetic interference and to charge influences from the oil fill and achieve good long-term stability, this pressure-measuring arrangement comprises: a pressure sensor having a base and an associated diaphragm with strain gages deposited thereon; a header of insulating material with leads and with an oil filler neck, said header of insulating material having the base mounted thereon, and said leads making electrical contacts to the strain gages; a metal body having a first central recess in a first cross-sectional surface, a second central recess in a second cross-sectional surface facing away from the first cross-sectional surface, and a hole connecting the first recess with the second recess, said first cross-sectional surface being tightly joined at its edge to the header of insulating material, and said first recess accommodating the substrate and diaphragm without touching them; an electrically conductive foil having an opening, said foil being disposed in the first rece

Abstract: A micromechanical structure or microactuator based upon the piezoelectric, pyroelectric, and electrostrictive properties of ferroelectric thin film ceramic materials such as PZT with a thickness between 0.1 and 10 micrometers. The thin film ceramic material is sandwiched between first and second electrodes and may contain an intermediate electrically insulating thin film. This structure with electrodes is formed on a deformable or movable structure integral to a semiconductor or bulk ceramic substrate. Electrical connection is established between the upper and lower electrodes. A potential difference or voltage is established between the electrical interconnection points to produce a force, movement, or mechanical deformation. The invention also relates to a method for making such micromechanical structures or microactuators.

Abstract: A method is disclosed for micromachining the surface of a silicon substrate which encompasses a minimal number of processing steps. The method involves a preferential etching process in which a chlorine plasma etch is capable of laterally etching an N+ buried layer beneath the surface of the bulk substrate. Such a method is particularly suitable for forming sensing devices which include a small micromachined element, such as a bridge, cantilevered beam, membrane, suspended mass or capacitive element, which is supported over a cavity formed in a bulk silicon substrate. The method also permits the formation of such sensing devices on the same substrate as their controlling integrated circuits. This invention also provides novel methods by which such structures can be improved, such as through optimizing the dimensional characteristics of the micromachined element or by encapsulating the micromachined element.

Abstract: A differential pressure transmitter detects a differential pressure condition of a fluid by means of a semiconductor sensor. First and second seal diaphragms are provided in a member which constitutes the differential pressure transmitter, to form first and second pressure receiving chambers. An overload protection diaphragm and first and second damper chambers are provided at positions close to the first and second pressure receiving chambers. Also, there are provided a passage for connecting the first pressure receiving chamber and the first damper chamber, a passage for connecting the second pressure receiving chamber and the second damper chamber, and passages for connecting the first and second damper chambers respectively with the semiconductor sensor. Even when a change is caused in the temperature of a processed fluid to be detected, the differential pressure transmitter quickly detects the temperature change, so that a differential pressure of the processed fluid can be measured with high accuracy.

Abstract: A differential pressure transmitter having a differential pressure sensor, a temperature sensor and a static pressure sensor all provided on the semiconductor substrate of a single semiconductor chip. A reference resistor is provided in a part of the chip. Resistances of the differential pressure sensor and the reference resistor are compared periodically in order to determine the condition including service life of the differential pressure sensor.

Abstract: A probe for monitoring a fluid medium employing at least one fiber optic emitting a wave into the fluid medium. The fluid medium scatters or causes luminescence of the emitted wave which is then collected by at least one fiber optic. The probe includes a base having a hole and a window covering the hole of the base, wherein the window transmits electromagnetic waves. The probe collects scattered and luminescence of waves through one or more fiber optics placed behind the window and transmits the waves to a spectrometer connected to a computer which can analyze the fluid medium on a real-time on-line basis. Piezoresistive and temperature sensing elements are deposited on the window which can also serve as a force collector diaphragm. The elements are located primarily on the periphery of the diaphragm leaving a part of the diaphragm open for transmission and collection of the waves.

Abstract: A semiconductor device comprises a piezoresistive pressure sensor (12), which has a membrane (14), which is constituted by a conducting epitaxy layer (16), which is applied to a conducting semiconductor substrate (18) of the opposite conductivity. On the outer surface (20) of the membrane facing away from the semiconductor substrate (18) at least one piezoresistor (22) is incorporated. Between the semiconductor substrate (18) and the epitaxy layer (16) an annularly structured intermediate layer (28) is incorporated, which defines a region (26'), adjoining the inner surface (24) of the membrane, of an opening (26) extending through the semiconductor substrate (18). This opening (26) is produced by anisotropic semiconductor etching, the intermediate layer (28) having a conductivity which is opposite to that of the semiconductor substrate so that this intermediate layer (28) functions as an etch stopping means and is not attacked by the etchant.

Abstract: In a pressure sensor, a force is transferred via a pressure plunger end made of relatively hard material onto a measurement element including a sensor membrane on a support. The sensor membrane is part of a micromechanical arrangement made of silicon. A metal structure made of a metal of lower hardness compared with the hardness of the material of the pressure plunger end is applied onto the sensor membrane. This metal structure can be impressed and plastically deformed with increased force by the contact surface of the pressure plunger end, in such a way that conforming contact of the contact surface is achieved, and potential angular errors are compensated for.

Abstract: A method for determining the volume a substance having a density level in vertical storage tanks. This method uses a strain gauge that is attached to the exterior of the side wall of a tank. As the volume of the substance fluctuates in the tank, the walls are acted upon by the weight of the substance. The greater the volume of a substance, the greater the force pushing on the tank walls and vice-versa. This force causes the walls to deform slightly. This deformation can be measured by the strain gauge mounted on the tank wall. Because this deformation is directly related to the volume of the substance being stored in the tank, the deformation read by the strain gauge can be translated into its volume by calibrating the gauge measurements with known volumes in the tank.

Abstract: A form of pressure sensor diaphragm and method of making that allows for the formation of long rectangular plate structures in semiconducting material, especially Silicon. A plurality or multiplicity of sensors may be constructed on a single chip, thus providing for absolute and relative sensing of pressure on a single device.

Abstract: A pressure sensor includes a diaphragm assembly with a pair of diaphragms joined together along a rim and having spaced apart centers to form a cavity between them. A pressure input applies a pressurized fluid to external surfaces of the diaphragms. The diaphragm assembly is connected to a mounting block along a tab leaving the remainder of the diaphragm free from solid mounting. Deflection of the diaphragm assembly is sensed and is related to applied pressure.

Abstract: A pressure sensor for fluids includes first, second, third and fourth strain gauges disposed on a diaphragm with prescribed spacing so that the majority of current flowing through the first strain gauge has a predetermined direction and the majority of current flowing through each of the second, third and fourth strain gauges has a direction identical with or opposite to the predetermined direction, first and second conductors interconnecting the first and second strain gauges and the third and fourth strain gauges, and first and second voltage leads connected to the first and second conductors from the side identical with or opposite to the direction of a vector product determined by a vector in the direction of current flow through the conductors and a vector in a direction normal to the diaphragm. The configuration causes voltages produced in the conductors by the Hall effect to cancel out, thus making the pressure sensor immune to the effect of magnetic fields.

Abstract: A media-isolated differential pressure sensor apparatus and corresponding method combines a first signal (207, 209) provided by a first pressure sensor (101), indicative of a difference between a first pressure and second pressure applied across the first pressure sensor, and a second signal (213, 215) provided by a second pressure sensor, indicative of a difference between the second pressure and a third pressure applied across the second pressure sensor (103) to form a differential pressure sensor. Responsive to a pressure span the first signal (207, 209) responds with a slope response different than a slope response of the second signal (213, 215). A slope adjustment circuit (217) enables an adjustment of the slope response of the first signal (207, 209) to correspond to the slope response of the second signal (213, 215), and provides a slope adjusted first signal (221) dependent on the adjusted slope response.

Abstract: An absolute pressure sensor subassembly includes a top cap bonded to a pressure sensor die and enclosing a reference vacuum. The subassembly is initially held in place within a housing by a vacuum or sublimeable solid adhesive while wire bonds from the subassembly to the housing leads are completed. A self-contained adhesive drop on the inner surface of the housing cover contacts the sensor subassembly when the cover is placed on the housing body and the sensor subassembly is supported by the adhesive drop.

Abstract: A differential pressure sensor (10) has a sensor die (16) attached to a stress isolation package base (12) with a bonding glass (27) having a similar coefficient of thermal expansion. The bonding glass, and alternately an aluminum layer, provides a hermetic seal between the stress isolation base and sensor die. Pressure is applied to the sensor die port (24). A plastic housing (14) is attached to the stress isolation base with an adhesive (29). A port (23) in the plastic housing is filled with a silicone gel (22). A second pressure source is transferred by way of the silicone gel to the sensor die. Any hostile chemical entering the via contacts the first surface of the sensor die to assert pressure against a transducer circuit (25) to generate the electrical signals representative of the applied pressure but are isolated from the sensitive interconnects by the hermetic seal.

Abstract: A pressure sensor is provided in which the pressure sensing components are isolated from a portion of an attached buffer member which is connected to a fluid conduit. The offset characteristic of the pressure sensor isolates stress from being transmitted between an attached external fluid conduit and the sensitive components of the pressure sensor. One embodiment of the pressure sensor solders a fluid conduit structure to a buffer member that is attached to a pressure sensor die. An alternative embodiment of the present invention avoids the need for making solder connections between the sensor structure and external components by utilizing elastomeric conductors and pressure seals in association with the pressure sensor composite structure and first and second housing structures. These elastomeric conductors also provide improved stress isolation. The housing structures are used to compress to the seal and the elastomeric conductor against selected portions of the composite sensor.

Abstract: A semiconductor strain sensor includes a base, a peripheral section, a central section and a flexible beam. The peripheral section is bent to the base. Bonding strain is generated at a bonding portion between the base and the peripheral section. The central section extends from the peripheral section. The flexible beam extends from the central section and includes a strain detecting element. The strain detecting element changes its electric characteristic when strain is applied thereto. A thickness of the flexible beam is thinner than that of the central section. The bonding strain is transmitted from the bonding portion to the strain detecting element through a transmission path. The transmission path is bent. The bonding strain is attenuated because it is dispersed at a bending portion of the transmission path. The sensor accurately detects the strain to be detected without a bad influence of the bonding strain.

Abstract: A semiconductor type differential pressure measurement apparatus is disclosed comprising a measuring diaphragm having its periphery fixed, and two measuring chambers, each having a predetermined spacing along both surfaces of the measuring diaphragm, and which detects differential pressure within allowable limits of measurement. When an overpressure is applied, the diaphragm is stopped by a wall of a measuring chamber to prevent the diaphragm from being damaged by overpressure, so that no additional mechanism is required to prevent damage from overpressure. One embodiment utilizes an additional chamber and overhang to reduce overpressure. Another embodiment utilizes a measuring chamber having the two sides of the diaphragm exposed to the ambient to eliminate need for a pressure resistant casing. In a further embodiment, injected impurities serve as a terminal.

Abstract: An apparatus (10) for use in inflating a vehicle occupant restraint (12) includes a pressure vessel (14) and a leakage detecting assembly (68). The pressure vessel (14) stores gas, and has a closure wall (40) which ruptures to release the gas from the pressure vessel (14) to inflate the vehicle occupant restraint (12). The closure wall (40) is movable under the influence of a change in the gas pressure within the pressure vessel (14). The leakage detecting assembly (68) senses movement of the closure wall (40) which occurs under the influence of a change in the gas pressure that is caused by leakage from the pressure vessel (14). The leakage detecting assembly (68) generates an electrical signal in response to such movement of the closure wall (40).

Abstract: A pressure transducer is provided with a housing member that attaches to a rigid and generally planar member, such as a ceramic circuit board. The legs of the housing member can pass through holes in the circuit board or, alternatively, can attach to edges thereof. The legs of the housing are provided with bails which have steps shaped to seize the circuit board after the legs are flexed to permit insertion of the board between them. The housing is provided with an opening that is shaped to receive a media seal, a pressure sensor die and a conductive seal between a surface of the opening and a surface of the ceramic circuit board. When the circuit board is attached to the housing, the seals and the pressure sensor die are compressed therebetween to provide good fluid sealing association between the components and to also provide electrical communication between components on the pressure sensor die and components on the circuit board.

Abstract: A force transducer comprising: a silicon semiconductor having a crystal face of (110); a pair of input-output shared electrodes mounted on the crystal face of the silicon semiconductor in mutual confronting relationship in a direction of <110> of the crystal or a direction equivalent to the direction of <110>; a force transmission block connected to the crystal face of the silicon semiconductor for transmitting a force W perpendicularly to the crystal face; and a support bed supporting the silicon semiconductor and connected to the silicon semiconductor at a face opposite to the crystal face to which the force transmission block is connected, whereby a voltage corresponding to the force W and to be measured is output from the input-output shared electrodes when the force W is applied perpendicularly to the crystal face of the silicon semiconductor via the force transmission block while a current flows in the silicon semiconductor via the input-output shared electrodes.

Abstract: A low range pressure sensor includes a base plate of brittle material, and a diaphragm plate mounted on the base plate and sealed around a periphery to the base plate. Pressures are introduced to cause the diaphragm to deflect toward the base plate, and the deflection of the diaphragm is sensed through strain gauges to provide an indication of the pressure. The diaphragm is provided with a plurality of individual support posts on a side facing the base plate, so that when the diaphragm is deflected toward the base plate under high overpressures the support posts will support the diaphragm against movement to avoid failure or breakage of the diaphragm. The number of support posts can be varied as desired.

Abstract: A resistive strain gauge pressure sensor including upper and lower housings coacting to define a pressure chamber within the housing. A board member assembly is clamped between the housings and defines a diaphragm portion which extends across the pressure chamber to divide the pressure chamber into upper and lower chamber portions. The board member assembly includes a relatively thin plate member, including a diaphragm portion, and a relatively thick support member bonded to the upper face of the thin plate member and including an annular portion positioned in surrounding relation to the diaphragm portion. The circuitry of the sensor is screen printed onto the lower face of the plate member and includes the various resistor elements of the strain gauge assembly, the various elements of the conditioning circuit receiving the output of the strain gauge assembly, and the various further leads required to connect the circuitry elements to the terminals of the sensor.

Abstract: A resistive strain gauge pressure sensor including upper and lower housings coacting to define a pressure chamber within the housing. A board member is clamped between the housings and defines a diaphragm portion which extends across the pressure chamber to divide the pressure chamber into upper and lower chamber portions. All of the circuitry of the sensor is screen printed onto the lower planar face of the board member including the various resistor elements of the strain gauge assembly, the various elements of the conditioning circuit receiving the output of the strain gauge assembly, and the various further leads required to connect the circuitry elements to the terminals of the sensor. The sensor terminals are provided by a plurality of connector pins extending downwardly through the board member for connection at their respective lower ends to the circuitry provided on the lower face of the board member.

Abstract: A pressure sensitive sensor in which a pressure detecting convex portion is formed on the surface of a pressure-sensitive and conductive elastomer sheet, and an electrode is arranged on the reverse side of the pressure detecting convex portion for making it possible to detect a pressure acting in the direction in parallel or in the oblique direction with a slight angle with respect to the surface of a pressure-sensitive and conductive elastomer component. In addition, for obtaining a high detection density, a contact is made up with a face-defined body defining a pressure face, and a contacting convex portion is made to protrude from the face-defined body, where the contact is resiliently supported onto the pressure-sensitive elastomer sheet.

Abstract: A transmitter with a flame arresting header senses a pressure of a process fluid with a diaphragm which is sealed to the header. The diaphragm transfers the pressure of the process fluid acting an outer surface of the diaphragm to a fill fluid that isolates an inner surface of the diaphragm, and a pressure sensor enclosed in the transmitter senses the pressure of the fill fluid providing an output representative of the pressure of the process fluid. The header includes a chamber on the header's outer face and a passageway extending from the chamber to a tapered opening inside the transmitter with a first portion adjacent to the tapered opening shaped to receive an inlet tube leading to the sensor and a second flame isolating portion open to the chamber. The fill fluid fills the chamber, the passageway, and the inlet tube and is sealed in with a tapered seal pressed into the tapered opening around the inlet tube.